A new study about wild bonobos reveals that females gain power over males not through size or strength, but by forming alliances. Reviewing three decades of data across six bonobo communities, researchers found that female coalitions are the key to their social rise, challenging assumptions about gender dynamics in the animal kingdom.
Strength in Numbers
Scientists have long debated why bonobo females, despite being smaller than males, often hold higher social ranks. By compiling demographic and behavioral data of the six communities over 30 years, researchers discovered that 85% of female coalitions target males. These team-ups help females win 61% of conflicts against males on average, with some communities reaching 98% to 100% female victory rates.
The study found that when females formed coalitions more frequently, they consistently outranked males. Even in groups where males occasionally claimed top spots, female alliances influenced power dynamics.
Credit: Natataek – CC BY-SA 3.0
Debunking Old Theories
The study tested three theories for female dominance. The self-organization hypothesis, which predicts male-heavy groups weaken male power, showed no link to female dominance when sex ratios were analyzed. Similarly, the reproductive control hypothesis, tying female power to synchronized fertility signals, also failed. The number of fertile females present didn’t boost their status.
Only the female coalition hypothesis held up. Even though male bonobos are physically larger, coalitions allowed females to overpower them. These alliances sometimes led to males avoiding groups for weeks after confrontations.
A Contrast to Chimpanzees
Bonobos’ teamwork-driven society starkly contrasts with chimpanzees, their closest relatives, where males dominate all females. Unlike male chimps, bonobo males rarely use aggression against females as a mating strategy, possibly to avoid provoking female coalitions.
Why It Matters
The findings give scientists a deeper understanding of social power dynamics in one of the closest living relatives to humans. The research shows coalitions enable females to overcome physical disadvantages, highlighting how social bonds — not just biology — drive hierarchy.
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“Drivers of female power in bonobos.” Surbeck et al. Communications Biology (2025).
